1. Technical Field
The present invention relates to a piezoelectric drive device, a robot, and a method for driving a piezoelectric drive device.
2. Related Art
Piezoelectric actuators (piezoelectric drive devices) that vibrate a piezoelectric body to drive a driven body (driven member) are used in various fields because a magnet or a coil is not necessary (e.g., JP-A-2004-320979). A basic configuration of this piezoelectric drive device is a configuration in which four piezoelectric elements are disposed in two rows and two columns on each of two surfaces of a reinforcing plate. The piezoelectric element is bonded to the reinforcing plate with adhesive or the like.
In the piezoelectric drive device, miniaturizing the piezoelectric element makes it possible to obtain relatively high power (large power-weight ratio (output per unit mass)). However, when the piezoelectric element is bonded to the reinforcing plate (vibrating plate) with adhesive or the like, bonding accuracy is an obstacle to the miniaturization. Moreover, since an adhesive layer is present between the piezoelectric element and the reinforcing plate, there is a problem in that transmission loss of drive power is inevitable.